{"id":24457,"date":"2017-06-26T06:57:02","date_gmt":"2017-06-26T06:57:02","guid":{"rendered":"http:\/\/blogs.agu.org\/landslideblog\/?p=24457"},"modified":"2017-06-26T06:57:02","modified_gmt":"2017-06-26T06:57:02","slug":"xinmo-landslide-2","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2017\/06\/26\/xinmo-landslide-2\/","title":{"rendered":"Xinmo landslide: an update"},"content":{"rendered":"
Xinmo landslide: an update<\/h5>\n

Whilst the search for survivors from the Xinmo landslide<\/a> in Sichuan Province, China continues, the reality is that there can now be almost no prospect of anyone else being found alive. This image, from Xinhua<\/a>, provides an indication of the scale of the problem facing the recovery teams:<\/p>\n

\"Xinmo

Recovery operations from the Xinmo landslide in China, showing the scale of the challenge. Image via Xinhua<\/a><\/p><\/div>\n

.<\/p>\n

Meanwhile, the Herald has published this image (via\u00a0AP Photo\/Ng Han Guan)<\/a> that provides a sense of the likely mechanism of this 8 million cubic metre landslide:-<\/p>\n

\"Xinmo

The Xinmo landslide in China, showing the slip surface. Image via Herald Net (AP \/ Ng Han Guan )<\/a><\/p><\/div>\n

.<\/p>\n

Above and behind the rescuer the slide plane is clearly visible – it appears to be an approximately planar rock surface, suggesting that this landslide was a translational slide on an existing defect.\u00a0 In the lower part of the hillside it has incorporated a large volume of weathered rick and colluvium.<\/p>\n

Meanwhile a kind reader has pointed out that the the history of large landslides, and of landslide dams, is described in a good Masters thesis – Song (2015)<\/a> – available on the University of Waterloo website<\/a>.\u00a0 This gives an estimated location for the 1933 Diexi earthquake, which is within a few kilometres of the Xinmo landslide, as the Google Earth image below shows:-<\/p>\n

\"Xinmo

Google Earth image showing the location of the Xinmo landslide in relation to the 1933 Diexi Earthquake<\/p><\/div>\n

.<\/p>\n

The lakes visible on this image were formed by landslides that blocked the valley during the Diexi earthquake.\u00a0 As I noted yesterday, the site of the Xinmo landslide appears to be an old landslide scar, one of several on that ridge:-<\/p>\n

\"Xinmo

Google Earth image of the Xinmo landslide site. Note the landslide scars extending to the ridge<\/p><\/div>\n

.<\/p>\n

These landslide scars extend right up to the ridge crest, which is a common feature of earthquake-triggered landslides.\u00a0 A good hypothesis therefore might be that the Xinmo landslide was a slide in an unfailed portion of a landslide triggered in the 1933 earthquake.\u00a0 Interesting, Song (2015)<\/a> reports that in the area around the town of Diexi:<\/p>\n

Orientation of these rock layers [is] mainly 170\u00b0in dip direction and 30\u00b0in dip angle.<\/span><\/p><\/blockquote>\n

If this is true at Xinmo as well, then this would explain the defect seen in the Herald Net image above.\u00a0 I have no doubt that the mechanisms of this landslide will be investigated by our colleagues in China, and will be published in due course.<\/p>\n

Reference<\/h5>\n

Song Ling (2015). Landslide damming in Western Sichuan Province, China, with special reference to the 1786 Dadu River and 1933 Diexi events<\/em>. UWSpace. http:\/\/hdl.handle.net\/10012\/9496<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

More information and imagery has emerged about the 8 million cubic metre Xinmo landslide in China, which killed over 100 people on Saturday<\/p>\n","protected":false},"author":22,"featured_media":24469,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[16,23,881,469,959],"class_list":["post-24457","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-landslide-report","tag-china","tag-earthquake","tag-east-asia","tag-featured","tag-landslide-report"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/24457","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/users\/22"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/comments?post=24457"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/24457\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/24469"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=24457"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=24457"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=24457"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}